JP5799159B2 - Wind power generator and operation method of wind power generator - Google Patents

Description

  The present invention relates to a wind turbine generator control method and a corresponding wind turbine generator.

  Wind turbine generators are generally known and are used to extract kinetic energy from wind, convert it to electrical energy, and power it to the power grid. At that time, the wind power generation apparatus also has a problem of protecting an electric power network to which the wind power generation apparatus supplies power.

  For example, the German patent application DE 100 22 974 A1 in 2000 (application publication date November 22, 2001) describes frequency dependent output regulation. According to this, when the power grid frequency rises, the output supplied by the wind turbine generator to the power grid is immediately reduced when the power grid frequency exceeds a predetermined threshold.

  This takes into account the power grid situation in which an excessive supply of energy occurs, which leads to an increase in the frequency handled by the invention described in the publication DE 100 22 974 A1, depending on the behavior of the large power plant.

  If there is a lack of energy supply or an increase in demand in the power grid, a frequency drop may occur, which could ideally be responded with an increase in the power supplied. However, it is difficult to increase the output to be supplied with one wind power generator. This is because the (one) wind power generator already supplies the maximum output that can be extracted from the wind in an optimal manner. Nevertheless, in order to be able to increase the output at least in a short time, for example, according to the German patent application DE 10 2009 014 012 A1, a short time can be achieved using the rotational energy accumulated in the moment of inertia of the rotor-generator system. It has been proposed to perform a time power increase. However, such methods must rely on the rotational energy stored in the rotor-generator system.

  Instead, the following publications are generally pointed out as further state of the art: DE 103 41 504 A1, WO 2011/000531 A2 and WO 2005/025026 A1.

DE 100 22 974 A1 DE 10 2009 014 012 A1 DE 103 41 504 A1 WO 2011/000531 A2 WO 2005/025026 A1

  It is therefore an object of the present invention to eliminate or ameliorate at least one of the above-mentioned problems. In particular, we propose a solution that proposes an improved possibility of power grid protection. At least, propose an alternative solution.

According to the invention, the method of claim 1 is proposed.
(Mode 1) In order to solve the above-mentioned problem, according to the first aspect of the present invention, there is provided a wind turbine generator having a generator having an aerodynamic rotor having an adjustable rotation speed and connected to a power grid. A control method is provided. In this way,
The wind power generator is operated at an optimal rotational speed at an optimal operating point for dominant wind conditions ;
The wind power generator is operated at a non-optimal rotational speed at a non-optimal operating point when switching operation, the non-optimal rotational speed is greater than the optimal rotational speed;
In the partial load operation, a first operation characteristic curve is set for adjusting each optimum operation point having the optimum rotation speed, and a second operation characteristic is used for controlling the wind turbine generator at the non-optimum rotation speed. A curve is used and the non-optimal speed is adjusted by the second operating characteristic curve;
-Based on the said 2nd driving | operation characteristic curve, it is adjusted to the larger rotation speed by the same output as the case of the corresponding optimal rotation speed in the said optimal driving | operation point.
(Mode 2) In the above method, when the wind speed decreases during the transition from the full load operation to the partial load operation, it is preferable that the output is initially reduced and the rotation speed is kept constant.
(Mode 3) In the above method, the wind turbine generator includes one or more rotor blades having adjustable rotor blade angles, and the rotor blade angle of the non-optimal operating point is It is preferable to change the rotor blade angle.
(Mode 4) In the above method, it is preferable that the switching of the operation is activated by receiving a notification signal, and the operation is switched from the operation at the optimal operation point to the operation at the non-optimal operation point.
(Mode 5) In the above method, the notification signal is preferably an external notification signal transmitted by a power network manager.
(Mode 6) In the above method, when the wind turbine generator is operated at the non-optimal operating point, kinetic energy is extracted from the wind turbine generator, and the kinetic energy is calculated by the wind turbine generator as the dominant wind. It is preferably used to supply more active power to the power grid in a short time than can be taken from the actual wind based on conditions.
(Mode 7) In the above method, the rotational speed of the wind turbine generator is at least the optimal rotational speed from the non-optimal rotational speed by taking out the kinetic energy for supplying the more active power to the power grid. It is preferable that it is lowered.
(Mode 8) In the above method, it is preferable that the non-optimal rotational speed is larger than the optimal rotational speed by about 0.5 to 1.5 revolutions per minute.
(Embodiment 9) A wind power generator having a generator having an aerodynamic rotor having an adjustable rotation speed and a control system, wherein the control system is the wind power generator according to any one of the above embodiments 1 to 8. It is preferably adapted to the operation of the device.
(Mode 10) In the wind power generator described above, it is preferable that a space between the aerodynamic rotor and the generator is configured by a direct drive system.
(Mode 11) In the wind turbine generator described above, the wind turbine generator is configured to have a FACTS function and / or rectifies the electric energy generated by the generator and is adapted to the frequency, voltage, and phase of the power grid. It is preferred to have one or more alternating current converters for converting to alternating current to power the power grid.
(Mode 12) A window including at least two wind power generators according to any one of the above modes 9 to 11 and at least one common power supply point for supplying electrical output of at least two or the two wind power generators A park is also preferred.
Furthermore, the following aspects are also preferable.
(Aspect 1) A method for controlling a wind turbine generator having a generator having an aerodynamic rotor having an adjustable rotation speed and connected to a power grid is provided. In this way,
The wind power generator is configured to be operable at an optimal rotational speed at an optimal operating point with respect to dominant wind conditions,
It is preferable that the wind power generator is continuously operated at a non-optimal rotational speed during a transition period or at a non-optimal operating point, and the non-optimal rotational speed is larger than the optimal rotational speed .
(Aspect 2) In the above method, in the partial load operation, a first operation characteristic curve is set for adjusting each optimum operation point, and the first operation characteristic curve is used for controlling the wind turbine generator at the non-optimal rotation speed. Preferably, a two operating characteristic curve is used and the non-optimal speed is adjusted by the second operating characteristic curve.
(Aspect 3) In the above method, when the wind speed decreases during the transition from the full load operation to the partial load operation, the output is initially reduced, particularly during the preset wind speed region, while the rotational speed Is preferably maintained constant.
(Aspect 4) In the above method, the wind turbine generator includes one or more rotor blades having adjustable rotor blade angles, and the rotor blade angle of the non-optimal operating point is It is preferable to change the rotor blade angle.
(Aspect 5) In the above method, in particular, the operation at the optimum operating point is changed to the operation at the non-optimal operating point, activated by reception of the notification signal, especially the external notification signal transmitted by the power network manager. It is preferable to be switched.
(Aspect 6) In the above method, when the wind turbine generator is operated at the non-optimal operating point, kinetic energy is extracted from the wind turbine generator, and the kinetic energy is calculated by the wind turbine generator as the dominant wind. It is preferably used to supply more active power to the power grid in a short time than can be taken from the actual wind based on conditions.
(Aspect 7) In the above method, the rotational speed of the wind turbine generator is at least the optimal rotational speed from the non-optimal rotational speed by taking out the kinetic energy for supplying the more active power to the power grid. It is preferable that it is lowered.
(Aspect 8) In the above method, it is preferable that the non-optimal rotational speed is larger than the optimal rotational speed by about 0.5 to 1.5 revolutions per minute, particularly about 1 revolution per minute.
(Aspect 9) A wind turbine generator having a generator having an aerodynamic rotor having an adjustable rotation speed is provided. The wind turbine generator is configured to be capable of operating at an optimal speed at an optimal operating point with respect to dominant wind conditions, and the wind turbine generator is continuously non-optimal during a transition period or at a non-optimal operating point It is preferable that the engine is operated at a rotational speed and the non-optimal rotational speed is larger than the optimal rotational speed.
(Aspect 10) In the wind power generator described above, in the partial load operation, a first operating characteristic curve is set for adjusting each optimum operating point, and the wind power generator is controlled at the non-optimal rotation speed. Preferably, the second operating characteristic curve is used, and the non-optimal rotational speed is adjusted by the second operating characteristic curve.
(Aspect 11) In the wind power generator described above, when the wind speed is reduced during the transition from full load operation to partial load operation, the output is initially reduced, particularly during a preset wind speed region, The rotational speed is preferably maintained constant.
(Aspect 12) In the wind turbine generator described above, the wind turbine generator includes one or a plurality of rotor blades having adjustable rotor blade angles, and the rotor blade angle at the non-optimal operating point is the optimum operation each time. It is preferable to change the rotor blade angle at a point.
(Aspect 13) In the wind power generator described above, the operation is performed by receiving, in particular, the notification signal, particularly the external notification signal transmitted by the power grid manager, from the operation at the optimal operation point to the non-optimal operation point. It is preferable to switch to operation.
(Aspect 14) In the wind turbine generator described above, when the wind turbine generator is operated at the non-optimal operating point, kinetic energy is extracted from the wind turbine generator, and the kinetic energy is controlled by the wind turbine generator. It is preferably used to supply more active power to the power grid in a short time than can be extracted from the actual wind based on the target wind conditions.
(Aspect 15) In the wind power generator described above, the rotational speed of the wind power generator is at least the optimum speed from the non-optimal speed by taking out the kinetic energy for feeding more active power to a power grid. It is preferable that the rotational speed is reduced.
(Aspect 16) In the wind power generator described above, it is preferable that the non-optimal rotation speed is larger than the optimal rotation speed by about 0.5 to 1.5 rotations per minute, especially about 1 rotation per minute.
(Aspect 17) In the wind turbine generator described above, it is preferable that no transmission mechanism is provided between the aerodynamic rotor and the generator.
(Aspect 18) In the wind turbine generator described above, the wind turbine generator is configured to have a FACTS function and / or rectifies the electric energy generated by the generator and is adapted to the frequency, voltage, and phase of the power grid. It is preferred to have one or more alternating current converters for converting to alternating current to power the power grid.
(Aspect 19) A wind park including at least two wind power generators according to any one of the above aspects 9 to 18 and at least one power supply point for supplying electrical output of at least two or the two wind power generators It is advantageous.

  Accordingly, a method for controlling a wind power generator having a generator and an aerodynamic rotor having an adjustable rotation speed and connected to the power grid is proposed. The aerodynamic rotor is to be distinguished from the electrodynamic rotor that is a component of the generator. The generator, and thus the entire wind power generator, is of the type configured to be adjustable in rotation speed. Accordingly, the rotational speed is not fixedly linked or linked to the frequency of the power network, which is also synonymously referred to as an electric network, but can be adjusted independently of the power network frequency.

  Such a wind turbine generator can be operated at the optimum operating point (operating point) for each dominant (dominant) wind condition and is usually operated as such. The prevailing wind conditions relate in particular to the prevailing wind speed, which will be considered below as the only feature of the prevailing wind conditions for the sake of brevity. In reality, however, additional conditions such as wind gustiness and air density should be considered, but are not considered here for the sake of brevity. Thus, basically, each wind speed can be assigned to one optimum operating point. In this case, the optimum operating point should be understood as the wind power generator taking out as much energy as possible from the wind and feeding it to the power grid. Boundary conditions such as the stability of the system and machine (mechanical) loads such as wind turbine depletion in particular are considered simultaneously. Such an optimum operating point is in particular characterized by a corresponding optimum rotational speed and optimum output (power) supply, which is sufficient for the following description. In this case, the output (power) supply (Leistungsabgabe) relates to the output (power) supplied to the power grid. In this case, the output (electric power) generated by the generator itself may be larger. This is because, for example, a loss can be subtracted from the output (power).

  Operating such a wind turbine at a non-optimal operating point during the transition period, even though such an optimal operating point due to the optimum speed exists for each wind turbine in principle for each wind speed. However, it is proposed according to the invention that the rotational speed at this non-optimal operating point, ie the non-optimal rotational speed, is greater than the optimal rotational speed at the optimal operating point of the dominant wind speed.

  Such operation at higher rotational speeds causes the wind turbines to add additional active power to the power grid, i.e., the active power that could actually be fed to the power grid based on dominant wind conditions, especially wind speed. It is proposed when it is expected or likely to supply more additional active power. In this case, i.e., especially during the transition period, the wind turbine generator is operated at a higher rotational speed, so that more kinetic energy is stored in both the aerodynamic rotor and the electrodynamic rotor of the generator. The transition period can in principle last for example 10-30 seconds, 2-10 minutes or 1-5 hours, or even 1-5 days. Here, the extent to which the operation at the non-optimal operation point is justified (allowed) with respect to the corresponding length of the transition period should be determined each time according to the situation. In principle, the wind turbine generator can be operated continuously even at a non-optimal operating point at which the rotational speed is increased. However, such operation can adversely affect the wind turbine generator as the sustained operation at non-optimal operating points becomes excessive (unverhaeltnismassig). However, such operation is technically possible.

  In principle, it is possible to operate the wind turbine generator at a rotational speed greater than the optimal rotational speed without reducing the output (electric power) fed to the power grid as compared with the optimal operating point. Nevertheless, this non-optimal operating point can be disadvantageous because an increase in rotational speed is accompanied by, for example, increased wear. Furthermore, an increase in rotational speed can be aerodynamically inconvenient because the operating point is less stable than the optimal operating point. For this reason, this may in some cases necessitate an increase in the adjustment (control) effort, and thus an increase in the input of control elements such as adjustment of the rotational moment or rotor angle, thus For example, wear can be increased.

  Advantageously, a (direct drive) wind power generator without a transmission mechanism (or transmission) is used. Such a transmission-equipped (direct drive) wind turbine generator has a very large moment of inertia of the generator rotor, which can be advantageously used to store kinetic energy. Thus, more kinetic energy can be stored by increasing the rotation speed. In this case, it should be taken into account that the kinetic energy stored in such a rotating member is proportional to the square of the rotational speed. The moment of inertia with which the stored energy is proportional increases with the fourth power of the radius for a homogeneous full cylinder. Therefore, a full cylinder with a diameter of 2 meters has a moment of inertia 16 times that of a full cylinder with the same material length and a diameter of 1 meter. It is clear from this that a wind turbine generator without a transmission mechanism can accumulate a lot of kinetic energy, and this accumulated kinetic energy becomes more excessive (over-proportional: ueberproportional) by increasing the rotational speed. It can be bigger.

  According to an embodiment of the present invention, it is proposed that the first operating characteristic curve be set (stored) in the wind turbine generator (hinterlegt) in order to adjust (determine) the respective optimal operating point in the partial load region. The The wind turbine generator can adjust (determine) the optimum operating point (one) each time using this operating characteristic curve. For this purpose, the operating characteristic curve can be set (stored) as a rotational speed-output characteristic curve. The transformation (Umsetzung) can be performed in such a way that the rotational speed is measured and the respective (corresponding) outputs are adjusted (determined) according to the operating characteristic curve. When, for example, more power can be extracted from the wind, the rotational speed further increases and the new power value is adjusted correspondingly according to the characteristic curve. The output can be adjusted (determined) by adjusting (determining) the rotational moment of the generator. The adjustment (determination) of the rotational moment depends on the type of wind turbine generator. If, for example, a synchronous generator with a direct current excitation rotor is used, the rotational moment is adjusted (determined) via a corresponding direct current for adjusting the excitation.

  Such an optimum operating characteristic curve is in principle arranged (plotted) with a number of optimum operating points which are each optimal for one dominant wind condition, in particular the dominant wind speed. Correspondingly, in this application, any or specific optimum operating point—this is reasonably valid for any or specific non-optimal operating point—in each case the dominant (dominant) It should be understood as wind conditions or wind speed. Thus, the optimum operating point does not mean the only absolute operating point for the wind turbine generator for a particular condition, but just one of many operating points for each actual wind condition.

  Such operating characteristic curves are set (stored) especially for partial load operation. In the partial load operation of the wind power generator with variable rotation speed dealt with here, the rotor blade angle is usually kept constant independently of the wind condition or wind speed for this partial load operation as long as it is adjustable. As already mentioned, only valid (reasonable) operating points, i.e. adjustments (determinations) of the output and the rotational speed, are carried out each time. Use the second non-optimal operating characteristic curve instead of the first optimal operating characteristic curve to adjust (determine) the increased rotational speed (increase in rotational speed) during the transition period in partial load operation. Is proposed. Then, based on this non-optimal operating characteristic curve, a larger rotational speed is advantageously adjusted (determined) with the same output as the corresponding optimal operating point. Accordingly, this second non-optimal operating characteristic curve is a lineup (plotted) of many non-optimal operating points each having a higher rotational speed than that of the corresponding optimal operating point. Therefore, the conversion of the operation of the wind turbine generator with the increased rotational speed can be executed in a simple manner in the partial load operation by setting (storing) the corresponding second operation characteristic curve.

  Furthermore, according to a further embodiment of the present invention, when the wind speed decreases, in the process of shifting from full load operation to partial load operation, the output is first reduced, especially during a preset wind speed region, The rotation speed is kept constant. Full load operation refers to operation at the rated output and rated speed when the wind speed reaches the value of the rated wind speed and the wind turbine generator is optimal. When the rotational speed is further increased, the rotor blade angle is changed, so-called pitching, which reduces the aerodynamic characteristics of the rotor (Aerodynamik) and reduces the energy extracted from the wind, thereby further increasing the rotational speed. Counteracts (blocks). When the wind speed decreases again and the wind turbine generator shifts from full load operation to partial load operation again, in this case, only the output is initially reduced, and the rotational speed is not yet reduced or a small amount compared to the normal case. It is suggested that only be lowered. To that extent, not initially reducing the rotational speed means that the rotational speed is reduced only when the wind speed falls below the rated wind speed by a preset value. To that extent, it should not be understood from the time point of view that the rotational speed is not initially reduced.

  Furthermore, according to an embodiment of the invention, it is proposed to operate the wind turbine generator at a rotational speed greater than the rated rotational speed during the transition period during full load operation. Such operation with an excessively increased rotational speed may shorten the life of the wind turbine generator and should therefore be kept as short as possible. Thus, the transition period should be kept as short as possible, for example only 10 minutes or only 1 minute.

  The wind turbine generator has one or more rotor blades having adjustable rotor blade angles (the rotor blade angle is adjustable), each time the rotor blade angle at the non-optimal operating point becomes the rotor blade angle at the optimal operating point. Conveniently changed. The use of a wind turbine generator having one or more rotor blades with adjustable rotor blade angles, to that extent, also describes the type of wind turbine generator. Adjustment of the rotor blade angle is to be understood as an active and deterministisch adjustment of the rotor blade angle. In other words, this relates to adjusting the rotor blade angle via a motor or other actuator. Advantageously, the wind turbine generator has a horizontal or substantially horizontal rotor shaft. This horizontal rotor shaft is also to be understood as a type of wind power plant, ie a so-called horizontal shaft-wind power plant. For example, a slight tilt angle of the rotor shaft with respect to the horizontal shaft by a slight angle, such as about 5 ° or 10 °, is also applicable.

  Adjustment (determination) of the rotational speed which is larger than the optimal rotational speed is therefore carried out via or using a corresponding rotor blade angle adjustment. Thus, the non-optimal operating characteristic curve in partial load operation may use a different rotor blade angle than that for the optimal operating characteristic curve. Furthermore, feedback control (Regelung) that is not assumed to have a constant rotor blade angle due to a non-optimal operating characteristic curve in part load operation, away from the optimal operating characteristic curve that is known and set (memory: hinterlegt). ) Can also be selected.

  Advantageously, the operation at the optimum operating point is switched to the operation at the non-optimal operating point. This is proposed, inter alia, for cases where increased kinetic energy is expected to be required. This switching can advantageously be activated by receiving a notification signal or a switching signal. Such a notification signal or switching signal can be transmitted from an external power network manager. The power network manager can transmit such a signal, for example, when observing that a need to protect the power network has arisen. Thus, for example, several special situations are known that can lead to or indicate a critical power grid condition. For example, the disconnection (cutting) of the power grid transmission cable, which is temporarily performed, for example, for repair purposes or for other reasons, can cause the power grid to fall into a critical state. For such a case, the power grid manager can transmit such a notification signal or switching signal to a wind park having a wind power generator or a plurality of wind power generators.

  Advantageously, when the wind turbine generator is operating at a non-optimal operating point, kinetic energy is extracted from the wind turbine generator, and the wind turbine generator is based on dominant wind conditions from the current (actual) wind. It is proposed to use this kinetic energy to power the grid for a short time with more active power than can be extracted. Thus, the kinetic energy stored in the wind power generator operating at an increased rotational speed is used to support the power grid.

  Advantageously, for this purpose, this kinetic energy extraction is carried out from the non-optimal speed to at least the optimal rotational speed by the extraction of kinetic energy so that the wind turbine generator speed supplies additional active power to the power grid. It is proposed to be implemented to be reduced. Advantageously, the rotational speed is reduced much more than the optimum rotational speed. Thus, first of all, the accumulated additional kinetic energy allows additional active power to be supplied to the power grid to support it, along with more than that obtained from the (actual) wind at that time ( Energy).

  Advantageously, the non-optimal speed is approximately 0.5 to 1.5 revolutions / minute greater than the optimal speed. More advantageously, the non-optimal speed is approximately 1 revolution / minute greater than the optimal speed. Thus, without operating the wind power plant at an excessively unfavorable operating point, in particular without causing excessive wear and without undue risk regarding the stability of the wind power plant, there is a significant increase in the rotational speed, and at the same time. A significant increase in kinetic energy can be proposed.

  The invention therefore relates to a method for controlling a wind turbine generator (Verfahren zum Steuern). In this regard, such control methods are generally as Steuerung, ie control that can have feedback, thereby forming feedback control (Regelung), or control that can be performed without feedback. Should be understood. In other words, feedback control (Regelung) is control with feedback (Steuerung), and thus includes predetermined control (in a loop with feedback). The concept of control is used as a generalized concept.

  Furthermore, the present invention proposes a wind power generator having a generator and an aerodynamic or aerodynamic rotor with adjustable speed, which is operated by the method of the present invention. In this case, it is advantageous to use a wind power generator without a transmission mechanism.

  According to an embodiment of the present invention, it is proposed that the wind turbine generator has a FACTS function. The name FACTS is an abbreviation for "Flexible-AC-Transmission-System" and is commonly used by those skilled in the art as a German usage. This is understood in the electrical energy technology as a control system used to target a power flow in a current supply network. Among other things, such a system can provide targeted active and / or reactive power. Furthermore, such feeding can be performed depending on the measurement in the power grid, so that it can respond directly to eg frequency changes. Thus, a wind power generator is proposed which can be introduced in an advantageous manner for power grid support. The strategy (possibility) of utilizing the increased rotational speed during the transition period provides a strategy (possibility) of using the increased energy in the form of kinetic energy for the power grid support. . This allows a system that supports such a power network to make use of additional active power for support and to supply the power network as needed.

  Advantageously, the wind turbine generator converts the generated electrical energy of the generator into direct current and converts it back into alternating current to feed the power grid, thereby adapting to the frequency, voltage and phase of the power grid. (Or inverter: Wechselrichter). If one has one or more such converters and ignores the losses, the wind power generator in which all the generated electrical energy is guided through the one or more converters is a so-called full inverter system (Vollumrichter-System). ).

  Furthermore, the present invention proposes a wind park comprising at least two wind power generators having the control method of the present invention. To that extent, Wind Park is a group of wind turbines connected to each other, in particular a common feed point or a plurality of common feed points for feeding electrical energy to the electrical network. It is. The advantages described for the method of the present invention and for the wind power plant of the present invention are integrated by this wind park, thus enabling a significant (significantly) reserve power to be made available.

  Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings.

An example of a horizontal axis wind power generator. An example of a graph having two rotation speed-output characteristic curves. Three examples of wind speed dependence graphs.

  FIG. 1 basically shows an example of a horizontal axis wind power generator known from the prior art. The horizontal axis wind power generator shown in FIG. 1 is configured to execute a predetermined method, that is, an operation management (control) method of the present invention according to the present invention.

  FIG. 2 schematically shows an example of two operating characteristic curves, that is, two rotational speed-output characteristic curves. In this graph, the optimum driving characteristic curve 1 is drawn with a solid line, and the non-optimal driving characteristic curve 2 is drawn with a broken line. The two operating characteristic curves 1 and 2 only show schematic transitions that may differ from the actual transitions. In particular, the actual transition can be different from a simplified linear graph. This graph should essentially explain the relationship between the optimum operating characteristic curve 1 and the non-optimal operating characteristic curve 2. In addition, this also applies to the graph of FIG. 3, which can be greatly simplified with respect to the actual transition as well.

  It can be found from the graph of FIG. 2 that the non-optimal operating characteristic curve 2 has a larger rotation speed n for the same output P than the optimal operating characteristic curve 1. Therefore, an increase in the rotational speed for each optimal rotational speed can be achieved by using the non-optimal operating characteristic curve 2 instead of the optimal operating characteristic curve 1.

Two operating characteristic curves 1 and 2 intersect at the rated point 4 the wind turbine generator is operated at the rated speed n _N and the rated output P _N. The operation at the rated point or the rated operating point 4 can be performed after the rated wind speed is reached. In order to avoid overloading of the wind turbine generator, neither the output P nor the rotational speed N should be increased beyond that. However, it may be possible to increase the rotation speed n at least for a short time depending on the situation. This situation is schematically shown by a selective characteristic curve portion 6 shown by a dotted line.

FIG. 3 shows three graphs for explaining an example of operation management (control) of the wind turbine generator. All three graphs each have one operating parameter that depends on the wind speed V _W , ie, the power output P for graph A, the wind power generator or aerodynamic rotor speed n for graph B, and the graph For C, the rotor blade angle α is shown. All graphs are based on the same horizontal axis where the wind speed is plotted.

Graph A shows a characteristic transition of the output P that depends on the wind speed V _W. Output (electric power) production is started at the time of start-up wind speed (Einschaltwindgeschwindigkeit) V _Wein . The output P increases to the rated output _{P N} of the time of the rated wind speed _{V WN.} This area is also referred to as a partial load area. From the rated wind speed _{V WN} up wind speed _{V Wmax,} the supply output P remains constant, the wind turbine generator supplies the rated output _{P N.} Maximum wind V _Wmax later, the output P is for protection of the wind turbine generator, the wind speed V _W is decreased further increased. As the rotational speed increases in accordance with the present invention, the output remains ideally unchanged in accordance with at least one embodiment, and to that extent, graph A is also non-optimal for use of the optimal operating point. Only one characteristic curve of the output P that is valid (applicable) for the use of the optimum operating point is shown. However, depending on the embodiment, it is possible that the output of the optimum operating point in each case is different from the output of the corresponding non-optimal operating point, in particular somewhat larger.

  A graph B schematically shows a transition of the rotational speed n as an example of the optimum rotational speed characteristic curve 31 drawn by a solid line and a transition of an example of the non-optimal rotational speed characteristic curve 32 drawn by a broken line. The two rotational speed characteristic curves 31 and 32 correspond to the output characteristic curve P of the graph A. However, in order to better explain the idea of the present invention, the graph is schematic and idealized. The same applies to the relationship.

According to the graph B of FIG. 3, the rotational speed corresponding to the non-optimal rotational speed characteristic curve 32 is the rotational speed corresponding to the optimal rotational speed characteristic curve 31 until the rated wind speed V _WN is reached, that is, in the partial load region. Exceeded (changes at a higher value). When reaching the rated wind speed V _WN , the wind turbine generator reaches its operating point. Therefore, the rotational speed n follows the optimum rotational speed characteristic curve 31 as well as the non-optimal rotational speed characteristic curve 32 drawn by the broken line. also it reaches a rated rotational speed n _n. Alternatively (instead) it is possible to further increase the rotational speed n beyond the rated rotational speed n _N , which is outlined by an alternative characteristic curve branch 34 drawn in dotted lines. Has been shown. In this case, an overload of the wind turbine generator with a correspondingly high rotational speed is accepted for at least a predetermined period.

In addition, the rotation speed n between the optimal operation and the non-optimal operation is the same in the full load region or the full load operation, that is, between the (rated) wind speed V _WN and the maximum wind speed V _Wmax , that is, the rated rotation speed n _N Have These (speed n of) is the same also for even or maximum wind speed V _Wmax greater wind speed so-called storm area (Sturmbereich) (match).

The output transition according to the graph A shown in principle and the rotational speed transition according to the graph B can be based on the transition of the rotor blade angle α according to the graph C. Graph C also schematically shows the materialized transition. The optimum rotor blade angle characteristic curve 41 is drawn as a solid line in the graph C. In the partial load region or partial load operation, that is, up to the rated wind speed V _WN , the rotor blade angle remains unchanged. In the full load region or full load operation, that is, after the rated wind speed V _WN , the rotor blade angle is increased in order to rotate the rotor blade for protection from wind. After reaching the maximum wind speed _VWmax , further and especially larger adjustments of the rotor blade angle are carried out in order to further protect the wind turbine generator. For full load operation, the term rotor blade angle decrease (Abfall) may be used instead of the term rotor blade angle increase (Anstieg), but this does not describe a different effect, just Only the nomenclature is different. Adjustment of the rotor blade angle in full load operation is commonly referred to as pitching, but is known in principle to those skilled in the art.

The non-optimal rotor blade angle characteristic curve 42 is drawn with a broken line and shows a rotor blade angle somewhat smaller than the optimum rotor blade angle characteristic curve 41 in the same region in the partial load region. This smaller rotor blade angle may initially be considered “(more) inconvenient”. In this case, a higher rotational speed can be achieved based on a smaller rotational moment or counter-moment (Gegenmoment). With a smaller generatormoment, which also represents a counter-moment, a higher speed can be generated as shown in graph B, but this can again cause a change in the inlet angle (Anstroemwinkel). . That is, the inflow angle depends not only on the wind speed VW but also on the speed of the rotor, and is synthesized in vector from these two speeds. In other respects, a generally known relationship between the output P, the rotational speed n and the rotational moment M is pointed out according to the following formula:

P = 2πnM

When the rated wind speed V _WN is reached, the rotor blade angle by the non-optimal rotor blade (angle) characteristic curve 42 matches the rotor blade angle by the optimum rotor blade angle characteristic curve 41. If a speed greater than the rated speed is to be used in the region of the rated wind speed V _WN , the rotor blade angle is not initially increased, i.e. not pitched, when the rated wind speed V _WN is reached. This is clearly indicated by an alternative characteristic curve branch 44 drawn in dotted lines. In this case, as described above, the overload of the wind turbine generator is accepted for at least a predetermined period.

  Thus, according to the invention, during the transition period, it is proposed to operate the wind turbine generator at at least a slightly increased rotational speed in order to make a predetermined energy reserve available as kinetic energy.

Claims (12)

Has a generator having an aerodynamic rotor with adjustable rotational speed, a control method of a wind power generators connected to the power grid,
The wind power generator is operated at an optimal rotational speed at an optimal operating point for dominant wind conditions;
- the wind turbine generator, upon switching of the operation, be operated in a non-optimum rotating speed in non-optimal operating point Rukoto it non optimal rotational speed is greater than the optimum rotating speed,
In the partial load operation, a first operation characteristic curve is set for adjusting each optimum operation point having the optimum rotation speed, and a second operation characteristic is used for controlling the wind turbine generator at the non-optimum rotation speed. A curve is used and the non-optimal speed is adjusted by the second operating characteristic curve ;
The method is characterized in that, based on the second operating characteristic curve, the engine speed is adjusted to a larger rotational speed with the same output as the corresponding optimal rotational speed at the optimal operating point . The method according to claim 1 , wherein when the wind speed decreases during the transition from full load operation to partial load operation, the output is initially reduced while the rotational speed is kept constant. The wind turbine generator has one or more rotor blades with adjustable rotor blade angles, the rotor blade angle of the non-optimal operating point being changed with respect to the rotor blade angle of the optimal operating point each time The method according to claim 1 or 2 , characterized in that: The method according to claim 1 , wherein the operation switching is activated by receiving a notification signal, and the operation is switched from the operation at the optimal operation point to the operation at the non-optimal operation point. The notification signal is an external notification signal transmitted by a power network manager.
The method according to claim 4. When the wind turbine generator is operated at the non-optimal operating point, kinetic energy is extracted from the wind turbine generator, which kinetic energy is extracted from the actual wind based on the dominant wind condition. than capable, short the method according to any one of claims 1 to 3, characterized in that it is used to power the more active power to the power grid. The rotational speed of the wind power generator is reduced from the non-optimal rotational speed to at least the optimal rotational speed by taking out the kinetic energy for feeding more active power to the power grid. The method of claim 6. The non-optimal rotational speed Method according to any one of claims 1 to 3, wherein greater than approximately per minute 0.5-1.5 rotation than the optimum rotating speed. In a wind turbine generator having a generator and a control system having an aerodynamic rotor with adjustable speed,
The said control system is adapted to the driving | operation of the said wind power generator by the method in any one of Claims 1-8 . The wind power generator characterized by these. The wind power generator according to claim 9 , wherein the aerodynamic rotor and the generator are configured by a direct drive system . The wind power generator is configured to have a FACTS function and / or rectifies the electrical energy generated by the generator and converts it to alternating current to power the power grid in a manner that matches the frequency, voltage and phase of the power grid. The wind power generator according to claim 9 or 10 , further comprising one or a plurality of AC converters. A wind park comprising at least two wind power generators according to any of claims 9 to 11 and at least one common feed point for feeding electrical output of at least two or two wind power generators.

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